π° Mortgage Payoff Calculator
See your real payoff date and how extra payments slash interest.
With your extra payments
Estimates for planning only, not financial advice.
The short answer: every extra dollar you pay goes straight to principal, shrinking the balance that next month's interest is calculated on. On a $100,000 balance at 6 percent with 30 years left, adding $200 a month pays the loan off in about 197 months instead of 360 and saves roughly $58,450 in interest. The earlier you start and the more consistent you are, the bigger the savings. Enter your balance above to see your own payoff date.
How to Use This Calculator
This calculator answers two questions: when will my mortgage be gone, and how much interest can extra payments save? Enter your current balance (not the original loan amount), your interest rate, and how many years are left. Add a monthly extra payment, a one-time lump sum, or both, and the calculator rebuilds your full payoff schedule month by month.
Enter your Current Loan Balance from your latest mortgage statement, your Interest Rate, and the Remaining Term in years.
Enter an Extra Principal amount per month, a One-Time Lump Sum applied in the first month, or both. Leave them at zero to see your current payoff path.
Read your payoff date, the months and years you save versus the scheduled payoff, and the total interest with and without the extra payments.
Scroll the month-by-month schedule to see exactly when each dollar of principal is paid, and download it as CSV for your own records.
The Math Behind Early Payoff
Every mortgage payment splits into interest (balance times the monthly rate) and principal (whatever is left). Extra payments skip the split entirely: the full extra amount reduces the balance, which means next month's interest charge is calculated on a smaller number. This is the compounding effect working in your favor. The earlier in the loan you add extra money, the more future interest each dollar destroys, because it removes interest charges from every remaining month of the loan.
Worked Example
Take a $100,000 balance at 6 percent APR with 30 years remaining. The scheduled payment is $599.55 a month. Paid on schedule, the loan runs the full 360 months and total interest is $115,838. Now add $200 a month in extra principal. The effective payment becomes $799.55, and the loan pays off in about 197 months (16 years and 5 months), more than 13 years early. Total interest falls to roughly $57,400, a savings of about $58,450. The month-by-month schedule above shows the balance dropping faster each year as the interest portion shrinks.
Lump Sum vs Monthly Extra: Which Wins?
Both work, but they win differently. On the same $100,000, 6 percent, 30-year loan:
| Strategy | Payoff in | Total interest | Interest saved |
|---|---|---|---|
| No extra payments | 360 months | $115,838 | $0 |
| $10,000 lump sum in month 1 | 279 months | $76,917 | $38,921 |
| $200/month extra | 197 months | $57,387 | $58,451 |
The lump sum is the most efficient per dollar: $10,000 once, placed in month one, kills interest for the maximum number of remaining months. The monthly extra wins on total savings here because it puts more cash in overall ($200 times 197 months is $39,400). My honest advice: if you get a windfall, throw it at the mortgage immediately rather than dribbling it out, since money today beats money next year. But for regular budgeting, the automatic monthly extra is the strategy people actually stick with, and the best strategy is the one you will not cancel. Try both in the calculator above and compare.
Extra Payment Strategies That Work
The most powerful strategy is also the simplest: a fixed extra amount every month, started as early as possible. If your budget is tight, even $50 a month on a typical loan saves thousands in interest and trims months off the term. A second approach is the biweekly trick: split your monthly payment in half and pay that every two weeks, which sneaks in one full extra payment per year without changing your monthly cash flow much. Windfalls work too. A tax refund, bonus, or inheritance applied as a lump sum early in the loan has an outsized effect, since it kills interest for the maximum number of remaining months.
One warning before you send extra money: confirm your loan has no prepayment penalty (most modern US mortgages do not) and make sure the extra is applied to principal, not held as a future payment. Write "apply to principal" on checks or select the principal-only option in your lender's portal, then verify on the next statement that the balance dropped by the full extra amount.
Recast: the Third Option Nobody Mentions
If you have a lump sum but want a lower payment instead of a faster payoff, ask your lender about a recast. You pay down a chunk of principal (often $5,000 or more), and the lender recalculates your monthly payment on the new balance while keeping your rate and term. The fee is small, usually around $250, and there is no appraisal or full refinance process. Recasting is ideal after a windfall when your priority is monthly breathing room rather than total interest. It does not shorten the loan the way extra payments do, so if your goal is being debt-free sooner, keep prepaying instead. And if your rate itself is the problem, a real refinance may beat both: check the math on our Refinance Break-Even Calculator.
Pay Off Early or Invest?
Paying extra on your mortgage is a guaranteed return equal to your interest rate. If your rate is 7 percent, every extra dollar earns a risk-free 7 percent by avoiding interest you would otherwise pay. Compare that with what the money could earn invested: over long periods, a diversified stock portfolio has averaged around 7 to 10 percent before inflation, but with real volatility and no guarantee. The right call depends on your rate, your timeline, and your comfort with risk. A common sensible order: keep 3 to 6 months of expenses in an emergency fund, capture your full 401(k) employer match, pay off high-interest debt like credit cards, and only then choose between extra mortgage payments and investing. Neither choice is wrong; both build wealth.
My take, since borrowers always ask for one: below 5 percent, favor investing after the 401(k) match, because the market's long-run return usually beats the guaranteed savings. Above 7 percent, favor the mortgage, because a guaranteed 7 percent risk-free is genuinely hard to beat. Between 5 and 7 percent, split the difference and sleep well either way. One more angle people miss: every extra mortgage payment also builds accessible equity. If disaster strikes after years of prepaying, a HELOC can tap that equity back. The money is not trapped; it is stored. For the full picture of your payment, see our Mortgage Payment Calculator, and for how each payment splits over time, the Loan Amortization Calculator.
Estimates for planning only, not financial advice.
Frequently Asked Questions
How does this mortgage payoff calculator work?
Enter your current loan balance, interest rate, and remaining term, and the calculator rebuilds your scheduled monthly payment from the standard amortization formula. Then it simulates every month, applying your extra payment (and any one-time lump sum) entirely to principal. The result is your real payoff date, the total interest you will pay with and without the extra payments, and how many months and dollars you save.
How much interest will extra payments actually save me?
More than most people expect, because every extra dollar skips all the future interest it would have accrued. On a $100,000 balance at 6 percent with 30 years left, the scheduled payment is $599.55 a month and total interest is $115,838. Add $200 a month in extra principal and the loan pays off in about 197 months instead of 360, and total interest falls to roughly $57,400, saving about $58,450. That is more than 13 years of payments erased.
Do extra payments shorten my loan or lower my payment?
On a standard fixed-rate mortgage, extra principal payments shorten the loan term; your required monthly payment stays the same, but you finish years earlier. The payment only drops if you formally recast (reamortize) the loan with your lender, which usually requires a lump sum and a small fee. If your goal is to be debt-free sooner, shortening the term is exactly what you want.
What is better: a monthly extra payment or one lump sum?
Both attack principal the same way, but timing matters. Money applied earlier in the loan saves more interest, because it kills the balance that every future month's interest would be charged on. A $12,000 lump sum in year one of a 30-year loan saves more than $200 a month spread over five years starting in year ten. If you have the cash now, lump sum wins; if not, a steady monthly extra is the next best thing.
What is mortgage recasting and is it worth it?
Recasting means paying a lump sum toward principal and having the lender recalculate your monthly payment on the new balance, keeping your rate and term. The fee is usually around $250 with no appraisal. It lowers your required payment instead of shortening the loan, so it is best when you want monthly breathing room after a windfall. If your goal is paying less interest overall, extra principal payments beat recasting.
Is there a prepayment penalty on my mortgage?
Almost certainly not. Federal rules banned most prepayment penalties on qualified residential mortgages after 2014, so modern US home loans let you pay extra or pay off early for free. A few non-QM or investor loans still carry them, so check your note or ask your servicer before sending a large lump sum. If a penalty exists, it is usually a percentage of the balance and only applies in the first few years.
Should I pay off my mortgage early or invest the money?
Compare your mortgage rate (after the mortgage interest tax deduction, if you itemize) against the return you reasonably expect from investing. Paying down a 7 percent mortgage is a guaranteed 7 percent return with zero risk, which beats most conservative investments. But if your rate is 3 percent and you have decades until retirement, investing often wins mathematically. Also keep an emergency fund and capture any 401(k) employer match before sending extra to the mortgage.
Do biweekly payments really make a difference?
Yes, but not because of magic scheduling. Paying half your mortgage every two weeks produces 26 half-payments a year, which equals 13 full monthly payments instead of 12. That one extra payment a year on a 30-year loan typically cuts about 4 to 5 years off the term. You can copy the effect yourself by dividing your monthly payment by 12 and adding that amount to each month's payment, with no special program needed.
Should I pay off my mortgage before retirement?
For most people, yes, if the math allows it. Entering retirement without a mortgage payment dramatically lowers the income you need, which can reduce your tax bill and how much you must withdraw from savings each year. The exception is a very low fixed rate: if you locked in under 4 percent, the cheap loan may be worth keeping while your investments compound. Run both scenarios in the calculator with your real balance and rate.
Will paying off my mortgage early hurt my credit score?
Slightly and temporarily. Closing your oldest installment account can trim a few points by reducing your credit mix and average account age. Most borrowers recover within months, especially with credit cards kept current. The small score dip is a poor reason to keep paying thousands in interest. If you plan to apply for new credit soon, time the final payoff for after the application.